﻿/*
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at 
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *  
 */

using System;
using java = biz.ritter.javapi;

namespace biz.ritter.javapi.util
{

    /**
     * An ListIterator is used to sequence over a List of objects. ListIterator can
     * move backwards or forwards through the list.
     */
    public interface ListIterator<E> : Iterator<E> {
    
        /**
         * Inserts the specified object into the list between {@code next} and
         * {@code previous}. The object inserted will be the previous object.
         * 
         * @param object
         *            the object to insert.
         * @throws UnsupportedOperationException
         *             if adding is not supported by the list being iterated.
         * @throws ClassCastException
         *             if the class of the object is inappropriate for the list.
         * @throws IllegalArgumentException
         *             if the object cannot be added to the list.
         */
        void add(E obj);

        /**
         * Returns whether there are more elements to iterate.
         * 
         * @return {@code true} if there are more elements, {@code false} otherwise.
         * @see #next
         */
        new bool hasNext();

        /**
         * Returns whether there are previous elements to iterate.
         * 
         * @return {@code true} if there are previous elements, {@code false}
         *         otherwise.
         * @see #previous
         */
        bool hasPrevious();

        /**
         * Returns the next object in the iteration.
         * 
         * @return the next object.
         * @throws NoSuchElementException
         *             if there are no more elements.
         * @see #hasNext
         */
        new E next();

        /**
         * Returns the index of the next object in the iteration.
         * 
         * @return the index of the next object, or the size of the list if the
         *         iterator is at the end.
         * @throws NoSuchElementException
         *             if there are no more elements.
         * @see #next
         */
        int nextIndex();

        /**
         * Returns the previous object in the iteration.
         * 
         * @return the previous object.
         * @throws NoSuchElementException
         *             if there are no previous elements.
         * @see #hasPrevious
         */
         E previous();

        /**
         * Returns the index of the previous object in the iteration.
         * 
         * @return the index of the previous object, or -1 if the iterator is at the
         *         beginning.
         * @throws NoSuchElementException
         *             if there are no previous elements.
         * @see #previous
         */
        int previousIndex();

        /**
         * Removes the last object returned by {@code next} or {@code previous} from
         * the list.
         * 
         * @throws UnsupportedOperationException
         *             if removing is not supported by the list being iterated.
         * @throws IllegalStateException
         *             if {@code next} or {@code previous} have not been called, or
         *             {@code remove} or {@code add} have already been called after
         *             the last call to {@code next} or {@code previous}.
         */
        new void remove();

        /**
         * Replaces the last object returned by {@code next} or {@code previous}
         * with the specified object.
         * 
         * @param object
         *            the object to set.
         * @throws UnsupportedOperationException
         *             if setting is not supported by the list being iterated
         * @throws ClassCastException
         *             if the class of the object is inappropriate for the list.
         * @throws IllegalArgumentException
         *             if the object cannot be added to the list.
         * @throws IllegalStateException
         *             if {@code next} or {@code previous} have not been called, or
         *             {@code remove} or {@code add} have already been called after
         *             the last call to {@code next} or {@code previous}.
         */
        void set(E obj);
    }
}
